Feeding pulverized fuel.



WITNESSES. i5

I FEEDING PULVERIZED FUEL.

APPLICATION FILED MAR. 12, 1914.

Patentd Apr. 11, 1916.

2 SHEETS-SHEET 1.

ATTORNEY.

C.J.GADD.

moms PULVERIZED run.

APPLICATION FILED MAR-1Z1 1914.

Patented Apr. 11, 1916.

2 SHEETS-SHEET 2- "-6 wmvsssss: I 9 7 0/ INVENTORY 04/10 15 Jay i6 1 ATTORNEY.

which carries it to a furnace,

i the top CHARLES J. GADD, OF LEBANON, PENNSYLVANIA.

FEEDING PULVERIZED E'UEL.

Specification of Letters Patent.

Patented Apr. 11, 1916.

Application filed March 12, 1914. Serial No. 824,091.

To all whom it may concern:

Be it known that I, CHARLES J. GADD, a citizen of the United. States, of Lebanon, in the'county of Lebanon and State of Pennsylvania, have invented certain new and useful Improvements in Feeding Pulverized Fuel, of which the following is a specification.

This invention relates to an apparatus for feeding pulverized fuel in regulated quantities from a hopper to a pressure blast pipe kiln or other place where it can be burned.

In the gravity feeding of pulverized fuel from a hopper, such material frequently forms a bridge or scaffold above the mouth of the hopper, and when such a scafiold breaks a large mass of the material sometimes flows into the feeding apparatus in excess of the amount required in regular feeding. It has been found that the material, owing to its weight .and slippery character will even force itself around through the spiral conduit of a spiral conveyer in advance of the movement of the spiral wing thereof and cause an irregular feeding. In open hearth furnaces especially this is not only objectionable but a fatal defect.

The principal object of the invention is to avoid the irregular in-rush referred to and to secure a steady feed of the material along channel-of the casing from the top opening thereof to a point in the descending leg thereof above the blast pipe, whence it passes in a falling stream across the blast pipe openings, and a take-up and return of that portion ofthe material which passes by said openings. A

In the accompanying drawings forming part of this specification and in which similar letters of reference indicate similar parts throughout the several views :--Figure 1, is a plan view of my pulverized fuel feeding apparatusi Fig. 2, a section of Fig. 1 on line line B-'B: Fig. 4, a section. of Fig. 2 on line G-C: Fig. 5, a side elevation of the device showing a means fordriving the feeding belt electrically: Fig.- 6, a front elevation showing two feeding belts placed side by side and staggered: Fig. 7, a side elevation of Fig. 6. I

The same reference numbers indicate corresponding parts in the different figures.

and a resident A-A: Fig. 3, a section of Fig. 2611 In the embodiment of the invention illustrated in the drawings, the apparatus comprises a chamber or case 1 consisting of an endless closed channel, constructed approximately in triangular form. The base of the triangle is at the top thereof and the apex at the bottom thereof." The endless channel is horizontal along the top of the case, a descending leg is connected with one end there of and an ascending leg connects the lower end of the descending leg with the top portion of the channel. The top is provided with an opening 2 which is surmounted by hopper 3, which serves to feed the material by gravity into the horizontal channel at the top of the casing. The descending leg is broadened laterally. V

Within the case 1 are three sprocket wheels 4-56 the journals of which are carried in castings 7- 8 which are securedto the sides of the case 1 by bolts 9 and passing around these wheels is a belt IQcarrying flights or scrapers 13.

10-11 is a' pressure blast pipe one end of which,as 10, enters one side of casing l and the other, as 11, enters the other side of the casing. As usual one end of the pressure blast pipe is connected with a blower and the other end is connected with a furnace in which the fuel is burned. Both the blower and furnace being well known and forming no part of my invention, are not illustrated.

The pulverized fuel drops from the hopper 3 through the opening 2 at the top of the case into the upper channel thereof and the flights of the endless chain conveyer carry it along said top channel past said opening to a point above the blast pipe in the descending leg of the case. The flights 13 practically fill the space between the opening 2 and the delivery point of the conveyer and serve as stops to prevent any sudden influx of material from the hopper to the .feeder.

The pulverized fuel falling from the belt '12 at the periphery of pulley 4 drops upon a guide plate 20, which maybe part of the 'portionof the fuel that is not drawn into pipe 11 falls to the bottom of case 2 where it is engaged by the flights 13 of the belt 12 casting of case 1, which directs it past the center of the sprocket 6 at the lower end of and is carried between these flights and the side of the case 1 up under the hopper 3 and is presently, together with the fuel dislodged from the hopper by the flights 13 as they pass beneath-it, droppeddown past the blast pipe when more or less of it is carried to the furnace.

It will be observed from Fig.2 that the the case 1 is placed to the right of the center line of the case,- and from Fig. 5 that the journals of this sprocket are carried ofi center by the castings 7. By taking out the stud bolts 9 which secure the castings 7 to case 1 and by moving these castings around so as to bring the bolt holes in them into register with other bolt holes 14: in the case 1 the journals of sprocket 6 are moved toward or away from the bottom of case 1 as may be necessary to adjust the tension of belt. 12.

At its bottom the case 1 carries a plate 15, v

held inplace by bolts 16, which can be removed to clean out the case when necessary.

The conveyer in the case 1 mayconsist of a single belt 12 as shown in Figs. 1, 2,3, and 5, or it may be made of two or more belts placed side by side as shown in Figs. 6 and '7." In thiscase the belts are arranged with their flights 13 staggered or alternately arranged so that the fuel will be delivered I by them alternately and with a more regular flow than is possible by a single belt.

The belt 12 is constructed of a number of links 21 which are pivotally connected as is usual in link belt constructions. It will be observed from Fig; 2 that the belt 12 is driven counter-clock-wise, as indicated by the arrow, and that when it passes over the pulley 4 that the change in direction of'the links 21 will cause the flights 13 to separate,

at this time the ends of the hooks 22 on one end of the links 21 are rotated around the pins 23'on-the adjacent end of the adjoining link and the fuel carried between the flights is thus disturbed and facilitated in falling from the belt as this latter passes down around the sprocket 4,

The outer and inner walls'24-25 of the case 1,, together with its side walls, may be, and preferably are, formed in a single casting to which is bolted the castings or plates 78 carrying the journals of the sprocket wheels carrying the belt. The inner wall of the case is provided with recesses 'at'the angles for the sprocket wheels.

The belt" 12 and its sprockets may be driven in any suitable manner. In the drawings, more particularly in Fig, 5 the shaft of sprocket 4 carries a gear wheell'i which'is driven by a gear wheel 18 carried upon the armature shaft of an electric motor 19. Any other means for the purpose may be employed, but the electricmotor drive'isof advantage asit makes a complete, self-contained and compact unit of each feeder.

arcane? po'site walls of said descending leg above the lower end thereof and below the upper end thereof and at one side of said endless conveyor, a hopper surmounting said chamber and opening into the top thereof, the

flights of said endless chain conveyer serving to practically close said channel between the hopper opening thereof and said descending leg, said endless chain conveyer passing above and below said blastv pipe openings and being operative to deliver fuel from said hopper into said descending leg above said blast pipe and to pick up and return the fuel which falls below said blast pipe, andmeans for driving said endless chain conveyer.

2. An apparatus fuel in regulated quantities comprising a chamber consisting of an endless closed channel including a descending leg of enlarged area and an ascending leg, an endless chain conveyer traversing said endless channel, a blast pipe connected with opposite openings of opposite walls of said descend-- ing leg above the lower end lthereof and below the upper end thereof and at one side of said endless conveyer,,a hopper surmounting said chamber and opening into the topthereof, the flights of said endless chain conveyer servingto practically close said channel between the hopper opening thereof and said descending leg, said endless chain conveyer passing above and below said blast pipe openings and being operative to deliver fuel from said hopper into saiddescending leg above said blast pipe and to pick up and return the fuel which falls below said blast pipe, an inclined guide plate above said openings, and means fordriving said endless chain conveyer.

3. An apparatus for feeding pulverized fuel in regulated quantities comprising a chamber consisting of an endless closed triangular channel including a descending leg of enlarged area and an ascending leg, an endless chain conveyer traversing said endless channel, a blast pipeconnected with opposite openings ofopposite walls of said descending leg above the lower end thereof and below the upper end thereof and under neath and atone side of said endless conveyer which passes through said leg onan inclined path, a hoppersurmounting said chamber and opening into the top thereof, the flights of said endless chain conveyer for feeding pulverized serving to ractically close said channel beturn' the fuel which falls below said blast tween the opper opening thereof and said pipe, and means for driving said endless descending leg, said endless chain conveyer chain conveyer. passing above and below said blast pipe CHARLES J. GADD.- 5 openings and being operative to deliver fuel Witnesses:

from said hopper into said descending leg C. F. ZIMMERMAN, above said blast pipe and to pick up and re- EUGENE HoAsTER.

Copies of this patent may be obtained for five cents each, by addressing the Oommiss1oner of Patents,

' Washington, D. 0. 

